The vulnerability resides in versions 1.0 and earlier of TLS, or transport layer security, the successor to the secure sockets layer technology that serves as the internet's foundation of trust. Although versions 1.1 and 1.2 of TLS aren't susceptible, they remain almost entirely unsupported in browsers and websites alike

Is this true? Are there any statistics that can confirm that many sites/webbrowsers are still using TLS 1.0?

2 Answers
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Yes, nearly everyone is still using SSL 3.0 or TLS 1.0. Ivan Ristic from Qualys did a nice talk at Blackhat about that this year.

As to whether or not the attack is real, I understand that it is indeed real, although there is some debate at the moment about its impact, since the details have not been made public yet.

UPDATE- We're recommending to our customers that they bump rc4 to the top of the ciphersuite list, since it won't be vulnerable to this attack. After a day's research, the attack looks both plausible and potentially severe.

RC4 is a stream cipher, and therefore doesn't use a construct like CBC. All block ciphers using CBC appear to be vulnerable. There aren't a lot of good references yet; this is largely the result of internal research and an emerging consensus on the Internet. Don't take my word for it, though - use this as a starting point to form your own conclusion.
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Steve DispensaSep 20 '11 at 22:20

For some very late-breaking stuff, several folks are talking about rc4 on twitter at the moment.
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Steve DispensaSep 20 '11 at 22:23